Method for producing cathodes and anodes for electrochemical systems, metallised material used therein, method and device for production of said metallised material

ABSTRACT

The invention relates to the production of composite cathodes, which comprise, for example, at least one lithium-containing spinel, composite anodes for lithium batteries, and the cathodes and anodes thereby produced. The active mass in the form of a thin film is incorporated into a material, or the active mass together with a matrix metal or a matrix alloy is deposited on a substrate. The invention also relates to a metallised, textile material made of insulating fibres which have been made conductive and which have been completely galvanically or electrolessly plated. The fibres lying on crossovers are not baked with other fibres, but can move freely. The surface of the material is thereby optimally used. Said material is preferably used as an anode or a cathode for batteries, especially a lithium battery, and fuel cells.

[0001] The invention relates to a method for depositing a coating onto asubstrate according to claim 1, a substrate thereby produced, as well asthe use of the substrate as a cathode in a lithium ion battery, a methodfor production of an active cathode or anode mass according to claim 28and/or 35, a method for production of a cathode and an anode with saidmass, the cathode and/or anode thereby produced, a metallized materialaccording to claim 46, a method for its production, as well as a methodfor execution of the last-mentioned method.

[0002] As the metallized material and its production plays a role in allaspects of the invention, it will be explained first.

[0003] In the present invention, the term galvanizing is understood tomean a current-supported electrolytic depositing of a metal or anon-metal, which is present as an ion in an aqueous solution, possiblyin combination with a dispersion of a material that is not soluble butis dispersible in the aqueous solution, onto a conductive substrate. Theterm electroless depositing refers to the depositing of a metal or analloy or a dispersed material onto a substrate, which is not supportedby external current, but is instead brought about by a reduction agent.

[0004] Here, the term “material” refers, for example, to a knittedfabric, a fleece, a woven fabric or similar material, while “fiber”refers, for example, to a filament or a combination of filaments. Theinvention preferably relates to a woven textile comprised of individualsynthetic filaments.

[0005] The attribute of a material is that it is essentially flat andhas relatively little depth. A material is by definition not rigid, butinstead more or less soft.

[0006] Materials that have been made electrically conductive are used intechnology in many different ways, such as in filter technology, inwhich a defined mesh width is a critical attribute. The use of such amaterial is especially important in the production of batteries, whereit is used in place of sheet metal or lattice electrodes, because itssurface is much larger and, moreover, its weight is lower.

[0007] For example, a mass carrier for electrodes of galvanic primary orsecondary elements from an open-mesh, three-dimensional networkstructure of synthetic threads coated with more or less conductive, thinmetal coatings, as well as electrodes made therefrom are known from DE195 03 447 A1. However, nothing is stated about the points ofintersection of the threads, especially not the fact that duringgalvanization they are moved relative to one another, so that it can beassumed that the points of intersection in the network structure arebaked.

[0008] Another material forming an electrode lattice, in the form ofneedled felt, is known from DE 40 04 106, and is needled twice toimprove its strength. However, this also makes the felt stiffer and moredense. During the initially chemical and subsequently galvanicmetallization, connecting metal nodal points which bake the fibers areproduced at intersecting fibers. Although these nodal pointsadditionally increase the stiffness of the felt in a manner, which is,in itself, desirable, they reduce the overall surface area.

[0009] Although such nodal points reduce the available surface of thefibers, they reliably establish a contact. Consequently, no efforts havethus far been undertaken to avoid their development.

[0010] In contrast, DE 27 43 768 describes a woven textile which ismetallized in an electroless immersion bath and with which the thicknessof the metal layer may not exceed 0.3 μm. Thus, the coated woven textileacts as a resistor to the flow of electric current, so that the known,coated woven textile is designed for electrically heatable clothing.Whether or not intersecting fibers are baked together duringmetallization is unforeseeable. However, baked areas would probablybreak during movement of the material, due to extremely thin layerthickness, so that the metallization would be incomplete in such areas.This does not impair the effect of the material acting as an electricresistor.

[0011] The invention is intended to improve the material of the typeinitially mentioned in one respect. In particular, its usability inbatteries is to be improved by enlarging the metallized surface.

[0012] According to the invention, this object is solved in that theentire surface of all fibers, including nodal points, is metal- oralloy-plated and the fibers are moveable relative to one another.

[0013] As a result of the fibers being coated on all sides, a maximummetallized surface is guaranteed, while the mobility of the fibersensures that this metal surface can also be utilized and is not reducedby, for example, fibers that are pressed tightly together, such as thosewhich inevitably occur in the needled felt disclosed by DE 40 06 106.The material of the invention can exhibit a geometry corresponding tothe respective purpose of use, wherein the mobility of the fibers doesnot mean that the material changes or impairs this geometry during use,but rather that the fibers are not pressed onto one another at thepoints of intersection to such an extent as to become immobile. Therange of mobility, in this case, can be extremely small.

[0014] The metallized fibers rest on top of one another at the points ofintersection and thus provide a sufficient electrical contact so that,contrary to expectations, no nodal points are necessary at which themetal coatings of the individual fibers are baked together.

[0015] Thus, in a preferred embodiment of this aspect of the invention,the entire surface of all fibers bears a galvanically or electrolesslyapplied metal or alloy coating. The points of intersection of the fibersare not baked together, but instead interlock while fully preserving thegeometry, wherein the electroless or galvanic coating of the fibers thathave previously been made conductive permits uniform application of themetal up to a preferred thickness of between more than 0.5 μm andapproximately 15 μm. A galvanic application is, in this case, preferablya crystalline metal coating, or so-called microstructure, while anX-ray-amorphous, glass-like structure always develops with anelectroless immersion bath. It has become apparent that thick,glass-like structures at intersections tend to bake and/or are soclosely adjacent to one another that the space between them is too smallto allow an electrolyte to penetrate into it, thus reducing the metallicsurface. How this problem can be corrected is demonstrated furtherbelow.

[0016] An especially preferred embodiment is one in which theinteraction between the mobility of the fibers and their crystallinecoating guarantees the full accessibility of the entire metal surface,while mobility can, if necessary, be restricted to a minimum level, sothat a woven textile according to the invention can also be used as aprecision filter, for example. During the preferred use of the materialof the invention as a battery electrode, the fibers can, however,exhibit a higher degree of freedom of motion. In this case, a glass-likecoating could also be used which, however, can also be produced bygalvanic means, such as in cases where special corrosion resistance isnecessary.

[0017] The thickness of the metal coating is preferably greater than 0.5μm and can range up to 15 μm.

[0018] All non-metallic fibers can be used as fiber material, althoughmineral fibers, ceramic fibers, glass fibers and synthetic fibers arepreferred. Of these [fibers], in turn, fibers of polyester,polytetrafluorethylene, polyamide, polycarbonate, polyethylenimine,polyethylene, polypropylene, polyvinylidene fluoride, aramide fibers,and/or perfluoralkoxy fibers are preferred.

[0019] Any metal can be used as the metal coating. Preferred are basemetals, especially Ni, Al, Co and Cu, alloys, especially NiPCo, NiPMn,NiP, FeNiCr, NiWo, NiPWo, NiSn, CoSn, NiMg and NiMo, and preciousmetals, especially silver, gold, platinum, palladium, ruthenium, andrhodium.

[0020] The preferred use of the materials of the invention, especiallywoven textiles, is their use as a functional material for microporouselectrodes in electrochemical systems, e.g., as a current deflectorand/or electrode material in Ni/MH batteries in battery production, aswell as an electrode in fuel cells, so that, as a result of the largesurface areas of the three-dimensional structures obtained and thetargeted control of the topography of the deposited metal coatings(targeted production of metallic coatings with very large surfaceareas), the efficiency and performance density of the systems listedabove can be substantially increased.

[0021] The active masses of the batteries (cathode and anode material)can be very effectively introduced into these microporous electrodes. Asa result, outstanding adhesiveness of the active materials can beachieved in lithium ion polymer systems.

[0022] Other preferred areas of application lie in filter technology,gas cleaning (O₂), alkalic water electrolysis (as positive and negativeelectrode), in weapons technology, security technology, and protectivework clothing, as well as in use as catalysts and resistance materialfor generation of heat and for ionizing air processing in air cleaningdevices.

[0023] Preferred battery types in which the metallized material of theinvention can be used are lithium ion, lithium ion polymer and NiMHbatteries, wherein the material serves as a current deflector andelectrode. The active masses are introduced into the materials.

[0024] The preferred fuel cell type is the low temperature PEM fuelcell.

[0025] In each case, the material structure is optimized in such a waythat the highest possible conductivity and largest possiblecatalytically active surface (for use as fuel cells and catalysts), aswell as largest possible active surface are achieved.

[0026] As indicated initially, a material of the invention cannot beproduced by means of known methods in which the entire material has beencoated electrolessly or, after it has been made electrically conductive,has been coated galvanically, since there will always be non-coatedzones at the points of intersection of the fibers.

[0027] A possible option would be to manufacture a metallized filamentand then to produce a material with this metallized filament. However,extreme care would be necessary during weaving of the material to avoiddamaging the metal coating which, after all, can be as thin as 0.5 μm.

[0028] According to the invention, therefore, the already finished[textile] material made of the materials described above is subsequentlytreated by initially etching and cleaning its surface and is then,possibly following activation with palladium, galvanically,electrolessly or, if applicable, mechanically (dusting of metal powder),or by means of sputtering, vaporizing or chemical vapor depositing(CVD), provided with an electrically conductive film until, finally, theactual metal coating is applied by electroless depositing orgalvanization. During this electroless depositing or galvanization, arelative motion of the fibers in the material is established, so thatthey are not at rest on top of one another, but instead are movedrelative to one another, so that no permanent points of intersection candevelop at which two fibers could become baked together and thereby forma metallic nodal point. The actual electroless application orgalvanization for production of the metallized materials of theinvention according to one of claims 46 through 51 takes place in amanner known in the art.

[0029] It was proposed some time ago (DB 22 39 547) to run a strandedconductor consisting of individual copper or other metal wires duringgalvanic tin-plating partially voltage-free, with alternating tensionand with alternating curvature, so that the individual wires aresubjected to a constant motion relative to one another while passingthrough the bath, as a result of which they can be galvanically coatedon all sides. However, the method of this publication is conditioned onthe metal wires being rigid, thus enabling the stranded conductors to berun voltage-free, which is not possible with a textile material.

[0030] The invention, however, has recognized that the fibers of amaterial, in spite of the requirement of said fibers being constantlyunder tension while being passed through a bath, can be subjected to areciprocal relative motion which is sufficiently large to ensure that,during electroless depositing or galvanizing, baking of the points ofintersection is avoided and error-free coating of all fibers on allsides is achieved. The production of the metallized material of theinvention was made possible in this manner. The production process isdiscussed in detail below.

[0031] Before a galvanic coating can be applied to a non-conductor, saidnon-conductor must first be provided with an electrically conductivefilm.

[0032] Electroless application of an electrically conductive film canconsist, for example, in the application of sulfides and polysulfides.In this process, cobalt, manganese, or stannous sulfides andpolysulfides are preferably applied to the surface of the material,followed by an intermediate rinsing process and subsequent immersioninto a sulfide-containing cross-linking solution, thereby generating afirmly adhering metal sulfide/polysulfide coating.

[0033] The conductive film can also be produced by vaporization orsputtering with a metal or by means of CVD.

[0034] However, it is also possible to divide this step into threesub-steps: conditioning, activation and electroless or galvanicmetallization of the surface. This will be discussed in greater detailbelow.

[0035] Prior to the electroless application of a sulfide/polysulfidefilm, and to sputtering, vaporization, CVD or conditioning, the surfaceis generally cleaned and etched, which prepares it for the subsequentsteps. This preparation is preferably accomplished by exposed thematerial to an atmospheric plasma.

[0036] This plasma is a non-thermal plasma. Due to a very highexcitation frequency ranging from several kilohertz to approximately 3gigahertz, and due to the resulting high field densities, anon-equilibrium plasma is achieved in which the electron energy in theplasma is greater than the energy of the ions and the excited particles.

[0037] The plasma consists of innocuous gases such as oxygen or air,whose physical and chemical action is based on the high particle energy.

[0038] The plasma gas, such as oxygen, nitrogen, argon, ammonia, CF₄ ora similar gas, is selected on the basis of the textile material. Duringactivation in microwave plasma, polar groups are incorporated on thematerial and/or fiber surface, generally the surface of a polymer. UVradiation forms polymer radicals in the plasma at room temperature,which react with the free radicals in the corresponding plasma gas. Thisresults in polar groups, such as hydroxyl, carboxyl or carbonyl groups,as well as amine groups, which are incorporated into the polymersurfaces. These effects are limited to the immediate surface zone (1 μmto 10 μm), so that the polymer body remains untouched.

[0039] Preferably, a plasma chamber is used which is accessible from twosides so that the material to be activated is continuously passedthrough the chamber and plasma. The height of the chamber is sufficientto allow for passage of any type of textile or fleece material. However,the chamber, which is open at both ends, has no seal, nor is itevacuated. However, the chamber walls are cooled so that a plasma withlong-term stability can be produced. The cooling system is preferably anair-cooling system.

[0040] The activation is preferably accomplished by means of a colloidalpalladium compound, such as that which is already fundamentally knownfrom DE 37 43 743. This method has proved to be advantageous over manyother known methods.

[0041] During electroless metallization, a metal ion derived, forexample, from a metal salt, is deposited electrolessly as a metal ontothe activated material by means of a reduction agent in a manner knownin the art. In one embodiment, the metal is identical to that which isapplied during an optional, subsequent galvanization. In this process,all chemically reducible metal ions can be used, i.e., including ions ofbase metals such as nickel and aluminum.

[0042] The metallization coating can be applied following activation orit can also be applied galvanically.

[0043] As already mentioned, the electrochemical aspect of theelectroless or galvanic application of the metal or alloy coating ontothe material substrate which has been made electrically conductive isknown in the art and widely described in the literature. In thisprocess, all metals and alloys mentioned above during the discussion ofthe material of the invention can be applied. Two exemplary electrolessapplications and two galvanic applications are described in thefollowing example.

[0044] As far as the simultaneous motion of the material duringelectroless or galvanic application is concerned, it is conceivable thatthe bath for the electroless or galvanic application (referred to in thefollowing as “electrolyte bath”) be used for motion, and that thematerial be placed in batches into a sort of galvanic “whirlpool.” This,however, would be a relatively non-productive process.

[0045] Accordingly, in the invention a more productive, continuousprocess is preferred in which a defined relative motion of all fibers isachieved by mechanically stressing the material as it is being conveyedthrough the electrolyte bath.

[0046] For this purpose, an apparatus is preferred in which the materialis conveyed over at least two rollers, at least one of which iselliptical. If two elliptical rollers are used consecutively, they mustpreferably possess the same rotation speed but, given their largecross-sectional axes, they may not be arranged in parallel.

[0047] During conveyance, the elliptical roller ensures that the segmentbetween two rollers covered by material constantly changes in rhythmicalfashion, so that the material is constantly expanded and then releasedconsecutively in the direction of conveyance. In the case of a woventextile, the warp threads are stretched and shift accordingly relativeto the woof threads.

[0048] It is also preferred to provide at least one additional rollerwhich features circumferential profiling progressing at a diagonal tothe circumference, such as diagonally progressing, elliptical grooves inthe cylindrical exterior surface of the additional roller. In the caseof a material in the form a woven textile, this roller grips the warpthreads and moves them in their longitudinal direction relative to thewoof threads.

[0049] As explained above, the motion of the warp threads relative tothe woof threads takes place in a defined manner. In the case of afleece, the threads are also moved relative to one another in the deviceof the invention, but in random fashion.

[0050] A preferred electrolyte bath according to the invention featuresa series of elliptical rollers arranged above the fluid level and,between each two elliptical rollers, an additional roller that ispositioned below the fluid level. Thus, the material runs in a zigzagpattern from one elliptical roller into the bath, onto an additionalroller, and from this roller out of the bath again, wherein the angle ofcontact of approx. 270° at each of the rollers permits the rollers tobecome fully effective. Following several immersion procedures, such asfive, the material runs out of the electrolyte bath, wherein each of thefibers is fully metallized and none of the fibers is baked to theremaining fibers.

[0051] Another aspect of the present invention relates to the productionof active masses in the form of a foil and the production of compositeelectrodes using these foils, wherein the composite cathode is a lithiumion cathode. A material provided with a metal or alloy coating by meansof electroless application or galvanization, which is structured andproduced as described above, except that the mobility of the fibersand/or the relative motion of the fibers during electroless or galvanicapplication is only an optional feature, is used as the substrate ormass carrier.

[0052] For the production of an active lithium ion cathode mass, atleast one lithium-containing spinel, which is preferably selected fromamong LiMn₂O₄, LiCoO₂, LiNiO₂, LiTiS₂ and LiVSe₂, is combined with highconductivity soot (which was obtained from Degussa AG, Germany) and anorganic binder such as polytetrafluorethylene or preferablypolyvinylidene fluoride (PVDF, obtained from Aldrich, Germany), which isinert under the operating conditions of an electrode. Subsequently, themixture is worked into a sufficient amount of high-boiling aprotic polarsolvent, such as N-methyl-2-pyrrolidinone (NMP, obtained from Aldrich,Germany), to achieve a homogeneous paste with a dough-like consistency.

[0053] Preferred amounts of the above components of the active lithiumion cathode mass are as follows:

[0054] Dry mixture:

[0055] Lithium spinel, preferably LiCoO₂, 55 to 75 wt. %, morepreferably 60 to 65 wt. %;

[0056] High conductivity soot: 25 to 35 wt. %, preferably 30 wt. %;

[0057] Inert binder, preferably polyvinylidene fluoride, 5 to 10 wt. %

[0058] (All percentages refer to the total weight of the dry mixture.)

[0059] High-boiling aprotic polar solvent, preferablyN-methyl-2-pyrrolidinone: 1-2 ml per 10 g of dry mixture

[0060] Using rollers, the above paste is rolled into a thin film with athickness of 300 to 500 μm, preferably 400 μm, and dried 16 to 30 hoursat 50 to 70° C., preferably approximately 20 to 24 hours atapproximately 60° C., whereby an active cathode mass in the form of athin film is obtained.

[0061] To produce the cathode, the active cathode mass in the form of athin film is worked, by means of calendaring, into a material coatedwith a metal or alloy coating suitable for a cathode.

[0062] This material can be produced in the manner described above underthe first aspect of the invention, wherein, however, the feature ofmobility of the fibers, i.e., the passing through of the electrolesscoating or galvanization during constant relative motion of the fibers,is optional.

[0063] Ni, aluminum and silver are preferred as metallic coatings forthe cathode. If nickel is used, it is preferable to protect the cathodewith a so-called primer to provide protection against corrosion byelectrolyte and conductive salts. The primer can, for example, be acarbon, which is precipitated, together with the metal, from a carbondispersion in a manner known in the art. However, a carbon layerconsisting of very fine carbon a few hundred nanometers in thickness(particle size ranging from 6-100 nm) can also be precipitated, alsofrom a dispersion, following completion of the nickel precipitation, orthe nickel coating can be additionally coated with a passivating coatingof aluminum, silver, an alloy or titanium with a thickness of 10 to 100nm to protect against corrosion.

[0064] The introduction of the active cathode mass into the cathode masscarrier (material coated with metal or an alloy) in the form of a thinfilm and by means of calendaring is performed at a temperature of120-150° C., preferably 130-140° C. Depending on the purpose ofapplication, a thin film cathode mass is applied to both sides of thematerial during this process. As a result of calendaring, the thin filmpenetrates through the openings in the material and surrounds it on allsides, especially when two thin films are used, resulting in amechanically highly stable composite cathode in which the active mass isoptimally distributed and no empty spaces exist between the deflectingmaterial (coated material) and the active mass. Accordingly, theinternal resistance of the composite cathode assumes very small values,which is extremely important in terms of the operating efficiency of arechargeable lithium ion battery.

[0065] To produce an anode mass in the form of a thin film, thefollowing components are initially mixed together:

[0066] 90-95 wt. % of graphite;

[0067] 5-10 wt. % of a binder, which is inert under the operatingconditions of an anode, such as polytetrafluorethylene or, preferably,polyvinylidene fluoride;

[0068] wherein the percentages refer to the total weight of this drymixture.

[0069] Subsequently, the dry mixture is worked into a sufficient amountof high-boiling aprotic polar solvent, preferably1-methyl-2-pyrrolidinone to achieve a homogeneous paste with adough-like consistency (generally 1-2 ml of solvent per 10 g of drymixture). Using rollers, the above paste is rolled into a thin film witha thickness of 300 to 500 μm, preferably 400 μm, and dried 16 to 30hours at 50 to 70° C., preferably approximately 20 to 24 hours atapproximately 60° C., whereby an active anode mass in the form of a thinfilm is obtained.

[0070] To produce the anode, the active anode mass in the form of a thinfilm is worked, by means of calendaring, into a material coated with ametal or alloy coating suitable for an anode.

[0071] This material can be produced in the manner described above underthe first aspect of the invention, wherein, however, the feature ofmobility of the fibers, i.e., the passing through of the electrolesscoating or galvanization during constant relative motion of the fibers,is optional.

[0072] Copper is generally used as a metal coating for the anode.

[0073] The introduction of the active anode mass into the anode masscarrier (e.g., material coated with copper) in the form of a thin filmis performed as with the introduction of the cathode mass into thecathode mass carrier described above. This results in anodes, whichexhibit outstanding properties similar to those of the cathodes producedin the manner described above.

[0074] In a complete rechargeable lithium ion battery system, the anodesand cathodes are separated by a separator made of microporous polymerfoil (e.g., Celgard® by Hoechst Celanese). To improve conductivity,minimum amounts of electrolyte, such as LP30 Selectipur® (Merck BatteryMaterials, Germany), are used. The separator foil is briefly soaked withelectrolyte and subsequently combined with the anode and cathode toconstruct a thin layer electrode stack for lithium ion batteries, asdepicted schematically in FIGS. 4 and 5.

[0075] A lithium ion battery produced with the thin layer compositeelectrode of the invention described above features significantly highercurrent densities and a relatively low weight when compared withconventional lithium ion batteries.

[0076] In a further aspect, the present invention relates to a methodfor producing a coating on a substrate, which comprises at least onelithium-containing spinel, wherein the lithium-containing spinel isapplied onto the substrate together with a metal or an alloy. Thesubstrate coating is applied electrolessly or galvanically from anaqueous solution of one or more ionic compounds of the metal or thealloy and a dispersion of the lithium-containing spinel(s), obtainedwith the aid of a tenside, in the solution, which thus becomes adispersion mixture.

[0077] The soluble ionic compounds of the metals and metal components ofthe alloys are commonly simple water-soluble mineral salts. The ioniccompound of the possible alloy component phosphorus is commonly ahypophosphite.

[0078] The substrate can, for example, be a material, which has beenmade conductive, of fibers that are inherently non-conductive, a metalfoil, or an expanded metal.

[0079] The material comprised of inherently non-conductive fibers or thesynthetic foil can, for example, be made conductive by means ofelectroless application or galvanic application of a conductive coating,which is selected from among metal, metal sulfide and/or polysulfide ora conductive polymer applied galvanically, electrolessly, or by means ofvaporization, sputtering, or CVD.

[0080] The material of the synthetic foil can comprise a material, whichis selected from among polyester, polytetrafluorethylene, polyamide,polycarbonate, polyethylenimine, polyethylene, polypropylene,polyvinylidene fluoride, aramide fibers, and perfluoralkoxy fibers.

[0081] The substrate is preferably a material comprised of inherentlynon-conductive fibers, which includes, in addition to fibers of thesynthetic materials mentioned above, glass fibers, mineral fibers andceramic fibers, which material is treated, prior to the electroless orgalvanic application of the coating of metal or alloy andlithium-containing spinel, in the manner described above in connectionwith the production of the inventive material.

[0082] The finely distributed spinel is kept in dispersion by adispergent, which is preferably an anionic tenside, such as acommercially available tenside in the Aerosol OT series (Cyanamid,Germany). During electroless precipitation or galvanization, it is thenincorporated, in finely distributed, dispersed form, into the metal orthe alloy, which forms a matrix with the spinel (precipitated from thewater-soluble ionic compounds). Up to 8% or more of spinel (relative tototal coating weight) can be incorporated into the matrix. The exactrate of incorporation can be controlled by parameters such as specialtenside additives, special precipitation temperatures, and specialconcentrations of the spinel dispersed in the solution.

[0083] The lithium-containing spinel(s) is(are) preferably selected fromamong LiMn₂O₄, LiCoO₂, LiNiO₂, LiTiS₂ and LiVSe₂.

[0084] In addition to the dispersed spinel, carbon dispersions and/ordispersions of an inert synthetic resin binder can also be present inthe dispersion mixture, and can be incorporated into the matrix metal orthe matrix alloy together with the spinel. The carbon protects againstcorrosion, and the inert synthetic resin binder serves, among otherthings, as a sort of “buffer” for the carbon, since, during use of theinventively coated substrates as lithium ion cathodes in a rechargeablebattery (secondary cell), the lithium ions intercalate in the carbonduring discharging of the battery and then diffuse out of the batterywhen it is charged, thereby changing the size of the carbon particles.This creates the risk of the carbon crumbling, which is eliminated bythe use of the binder.

[0085] Polytetrafluorethylene and, especially preferably, polyvinylidenefluoride can, for example, be used as the inert synthetic resin binder.

[0086] A carbon with a size in the nanometer range is preferably used asthe carbon.

[0087] In addition, the dispersion mixture also generally contains anacid, preferably boric acid. A hypochlorite can also be present in themixture as a reduction agent.

[0088] The electrolessly or galvanically applied matrix metals or matrixalloys are preferably selected from among Ni, Cu, Al, Co, Ag, Au, Pt,Pd, Ru, Rh, NiPCo, NiPMn, NiP, FeNiCr, NiWo, NiPWo, NiSn, CoSn, NiMg,and NiMo.

[0089] In light of the use of the coated substrate as a lithium ioncathode, the coating especially preferably comprises a metal selectedfrom among Ni, Al, and Ag.

[0090] For purposes of passivation, the coating can also be providedwith an additional coating of aluminum, silver, an alloy, or titaniumwith a thickness of 10 to 100 nm, or with carbon, as has already beendescribed above in connection with the thin layer composite cathodes.This is especially advantageous with a coating that contains nickel.

[0091] The volumes of reagents in the dispersion mixture used duringgalvanization generally fall within the following ranges:

[0092] soluble ionic compound(s) in a total volume of 240 to 380 g/l ofdispersion mixture;

[0093] the lithium spinel(s) in a volume of 100 to 300 g/l of dispersionmixture;

[0094] the tenside in a volume of 1 to 2 ml/l of solution;

[0095] carbon, if used, in a volume of 1 to 5 g/l of dispersion mixture;

[0096] inert synthetic resin binder, if used, in a volume of 5 to 10 g/lof dispersion mixture;

[0097] boric acid in a volume of 10-60 g/l of dispersion mixture

[0098] hypophospite, if used, in a volume of 10 to 60 g/l of dispersionmixture.

[0099] In addition, the pH of the dispersion mixture duringgalvanization is preferably 3-4, and the temperature at which theprecipitation is performed is, for example, 40-55° C. The currentdensities used fall within a range of 1 to 10, preferably 2 to 5 A/dm².

[0100] The thickness of the precipitated coating preferably ranges from0.5 μm to 15 μm.

[0101] Several of such coating layers can also be applied to asubstrate.

[0102] The invention also relates to a substrate comprised of a materialof non-conductive fibers which has been made conductive, a syntheticfoil which has been made conductive, a metal foil or an expanded metalwhich features a coating comprising a metal or an alloy and one or morelithium-containing spinels embedded into the metal or the alloy. Themetal of the alloy used in this process is preferably selected fromamong Ni, Cu, Al Co, Ag, Au, Pt, Pd, Ru, Rh, NiPCo, NiPMn, NiP, FeNiCr,NiWo, NiPWo, NiSn, CoSn, NiMg and NiMo, and the spinel(s) is(are)preferably selected from among LiMn₂O₄, LiCoO₂, LiNiO₂, LiTiS₂ andLiVSe₂.

[0103] The non-conductive fibers of the material preferably compriseglass fibers, mineral fibers, ceramic fibers, or synthetic fibers. Thesynthetic fibers preferably comprise a material selected from amongpolyester, polytetrafluorethylene, polyamide, polycarbonate,polyethylenimine, polyethylene, polypropylene, polyvinylidene fluoride,aramide fibers, and perfluoralkoxy fibers.

[0104] The coating can further contain carbon, an inert synthetic resinbinder, which is preferably polyvinylidene fluoride.

[0105] The coated substrates obtainable by means of the method describedimmediately above are preferably used as cathodes in lithium ionbatteries. The advantages of these cathodes consist in the fact that theactive mass can be applied, together with the material which isessential for deflection, in a desired layer thickness, which results ina highly compact composite material with a practically pore-freecoating.

[0106] Anodes that can be used in a lithium ion battery can also beproduced by means of dispersion precipitation onto one of the substratesspecified above. A typical example of this is an anode coated withcopper/graphite.

[0107] In this process, the composition of the dispersion mixture forgalvanic precipitation is, for example, as follows:

[0108] 160 to 240 g/l of a soluble copper salt, such as copper sulfate

[0109] 40 to 100 g/l of sulfuric acid

[0110] 30 to 150 mg/l of a chloride (e.g., sodium chloride)

[0111] 100 to 150 g/l of graphite, and

[0112] 1-2 ml/l of tenside.

[0113] In this case, the galvanization process is preferably performedat a temperature of 20 to 40° C. and a current strength in the range of1 to 10, preferably 2 to 5 A/dm². At the graphite quantities indicatedabove, incorporation rates (of graphite into copper) of 1.5 to 3 wt. %relative to the total weight of the coating can be achieved.

[0114] Using these cathodes and anodes, which generally contain, in asingle layer, the conductive material needed for deflection and theactive cathode and/or anode mass, a complete lithium ion battery can beproduced, in a manner similar to that discussed above in connection withthin layer composite foil lithium ion batteries. In this process, theanodes and cathodes feature maximum compactness and a practicallypore-free coating.

EXAMPLE

[0115] 1. Etching and cleaning

[0116] The material comprised of electrically non-conductive fibers isexposed to an atmospheric plasma in the manner described above. Thiscleans and etches the surface, making it receptive to additionaltreatments.

[0117] 2. Conditioning of the surface

[0118] In an activator with the following composition:

[0119] 0-5% 2-propanol,

[0120] 10-25% 2-amino-ethanol,

[0121] at a temperature of 50-80° C. and for a period of 5-10 min.,uniform coverage of the fiber surface is achieved, and absorption of thepalladium cores in the following step is supported.

[0122] 3. Activation on the basis of colloidal palladium compound

[0123] During activation of the fiber surface, colloidal palladiumcompounds are absorbed at the surface. The following compounds are used:

[0124] 6 g/l of stannous chloride

[0125] 20-400 ppm of palladium

[0126] The temperature ranges from room temperature to 50° C. Thetreatment lasts 3-10 min.

[0127] 4. Electroless (chemical) metallization

[0128] Copper electrolyte example:

[0129] 10-50 g/l of copper sulfate

[0130] 10-50 g/l of Rochelle salt

[0131] 5-20 g/l of sodium hydroxide solution

[0132] 10-100 g/l of formaldehyde

[0133] pH value: 10.5-12.5

[0134] Temperature: 20-50° C.

[0135] Duration: 1-10 min.

[0136] Nickel electrolyte example:

[0137] 10-30 g/l of nickel sulfate

[0138] 10-50 g/l of sodium hypophosphite

[0139] 50-100 g/l of ammonia (25%)

[0140] pH value: 8-10

[0141] Temperature: 30-50° C.

[0142] Duration: 3-10 min.

[0143] Galvanic metal application

[0144] Copper electrolyte example:

[0145] 60-249 g/l of copper-(II)-sulfate-5-hydrate (corresponds to 20-60g/l of Cu)

[0146] 40-200 g/l of sulfuric acid

[0147] 30-150 g/l of chloride

[0148] Wetting agent

[0149] Temperature: 20-35° C.

[0150] Current density: 1-8 A/dm²

[0151] Nickel electrolyte example:

[0152] 240-310 g/l of nickel sulfate

[0153] 45-50 g/l of nickel chloride

[0154] 30-40 g/l of boric acid

[0155] Wetting agent

[0156] pH value: 3-5

[0157] Temperature: 40-70° C.

[0158] Current density: 3-10 A/dm²

[0159] A schematic exemplary embodiment of a device for metallizingmaterial according to the invention as well as a schematic depiction oflithium ion batteries are shown in the enclosed drawing, in which

[0160]FIG. 1 shows a sectional general depiction of the device,

[0161]FIG. 2 shows an enlarged, sectional depiction of the rollersequence in the galvanic bath,

[0162]FIG. 3 shows an aerial view of the lower roller of the rollerseries depicted in FIG. 2,

[0163]FIG. 4 shows a schematic, exploded view of a lithium ion batterywith think layer composite electrodes, and

[0164]FIG. 5 shows a schematic, sectional view of a lithium ion batterywith thin layer composite electrodes.

[0165]FIG. 1 shows a device for producing a metallized material. A woventrack of synthetic material 10 is disposed on an unrolling supply roll11 and moves continuously in the direction of the arrow and,consecutively,

[0166] through a plasma chamber 1, in which atmospheric plasma acts onthe material 10, and cleans and activates it,

[0167] through a conditioning bath 2, which opens the fiber surface andprepares it for the subsequent activation,

[0168] through a rinsing bath 3,

[0169] through an activation bath, in which colloidal palladiumcompounds are absorbed at the surface,

[0170] through an electroless (chemical) metallizing bath, in which thesurface of the fibers is made conductive,

[0171] through an additional rinsing bath 6,

[0172] through a galvanic or electroless electrolyte bath 7, in whichmetal application to the fibers take place,

[0173] yet another rinsing bath 8, and

[0174] a horizontal drying shaft 9

[0175] onto the take-up roll 12.

[0176] The conveyance paths in the atmospheric plasma chamber 1 and thedrying shaft 9 are positioned at the same level. Also at this level,diversion rollers 13 are arranged which divert the horizontally arrivingmaterial 10 into the underlying bath 2-8 or steer the material 10emerging from this bath 2-8 into the horizontal [plane] and to the nextdiversion roller 13.

[0177] At least one immersion roller 14, whose axis runs in parallel tothat of the diversion rollers 13 and take-up rolls 11, 12, is disposedin each bath 2-8 in proximity to the floor of said bath. In each of thebaths 2-6 and 8, an immersion roller 14 is disposed to which twodiversion rollers 13 are assigned; five immersion rollers 14, to whichsix diversion rollers 13 are assigned, are disposed in the electrolytebath 7.

[0178] The material 10 rolls off the roll 11, passes through all bathsin a zigzag pattern, passes through the plasma chamber 1 and the dryingshaft 9 horizontally, and is taken up onto the roll 12.

[0179] At least the diversion rollers 13, which are assigned to theelectrolyte bath 7, feature an elliptical profile. The two diversionrollers 13, each of which is assigned to an immersion roller 14, arearranged in profile in such a way that the large axes of the ellipticalprofile are positioned vertical to one another (FIG. 2).

[0180] The immersion roller 14 can be spring-loaded in a downwarddirection, so as to keep the track of material 10 tightly spanned at alltimes.

[0181] The immersion roller 14 features circumferential profiling in theform of elliptical, i.e., diagonally arranged grooves 15 (FIG. 3).

[0182] When the track of material 10 runs across the rollers 13 and 14,which are shaped as depicted in FIG. 2 and 3, the track 10 isrhythmically stretched between adjacent elliptical rollers 13 and, atthe same time, moved in a lateral direction by the profile 15 of theimmersion roller 14. The material “breathes,” in a manner of speaking,as it moves across the rollers 13, 14.

[0183] These specially shaped rollers 13 and 14 are primarily assignedto the electrolyte bath 7, where they must ensure that fibers are notbaked together at points of intersection. However, they are also usefulin the other baths 2 - 6 and 8, as the motion of the fibers promotesrapid coating of the material 10 in each respective bath, therebypermitting more uniform and expeditious processing of the material 10.

[0184] Individual rollers or all rollers 13, 14 can be [mechanically]driven, as can the take-up roll 12. The feed roll 11 can be providedwith a brake. The height of the rollers 14 can be adjusted individually,so as to adjust the dwell time of the material 10 in the applicablebath.

1. Method for depositing a coating, which comprises a metal or an alloyand one or more lithium-containing spinels, onto a substrate,characterized in that the coating is applied electrolessly orgalvanically from an aqueous solution of one or more soluble ioniccompounds of the metal or the alloy and a dispersion of thelithium-containing spinel(s), obtained with the aid of a tenside, in thesolution, which thus becomes an aqueous dispersion mixture.
 2. Methodaccording to claim 1, characterized in that the substrate is a materialof inherently non-conductive fibers, which has been made conductive, asynthetic foil, which has been made conductive, a metal foil or anexpanded metal.
 3. Method according to claim 2, characterized in thatthe material or the synthetic foil is made conductive by means ofelectroless application or galvanic application of a conductive coating,which is selected from among metal, metal sulfide and/or polysulfide ora conductive polymer applied galvanically, electrolessly, or by means ofvaporization, sputtering, or chemical vapor depositing (CVD).
 4. Methodaccording to one of claims 1 through 3, characterized in that carbon isalso dispersed in the dispersion mixture which is deposited,electrolessly or galvanically, simultaneously with the metal or thealloy and the spinel(s).
 5. Method according to one of claims 1 through3, characterized in that an inert synthetic resin binder is alsodispersed in the dispersion mixture which is deposited, electrolessly orgalvanically, simultaneously with the metal or the alloy, the spinel(s)and, if applicable, the carbon.
 6. Method according to [claim] 5,characterized in that the inert synthetic resin binder ispolytetrafluorethylene or polyvinylidene fluoride.
 7. Method accordingto one of claims 1 through 6, characterized in that the tenside is ananionic tenside.
 8. Method according to one of claims 1 through 7,characterized in that the metal or the alloy is selected from the groupconsisting of Ni, Cu, Al Co, Ag, Au, Pt, Pd, Ru, Rh, NiPCo, NiPMn, NiP,FeNiCr, NiWo, NiPWo, NiSn, CoSn, NiMg, and NiMo.
 9. Method according toclaim 8, characterized in that the coating comprises a metal that isselected from the group consisting of Ni, Al, and Ag.
 10. Methodaccording to one of claims 1 through 9, characterized in that thecoating is coated with an additional coating of aluminum, silver ortitanium with a thickness of 10 to 100 nm, or carbon.
 11. Methodaccording to one of claims 1 through 10, characterized in that thelithium-containing spinel is selected from the group consisting ofLiMn₂O₄, LiCoO₂, LiNiO₂, LiTiS₂ and LiVSe₂.
 12. Method according to oneof claims 2 through 11, characterized in that the material or thesynthetic foil comprise a material which is selected from the groupconsisting of polyester, polytetrafluorethylene, polyamide,polycarbonate, polyethylenimine, polyethylene, polypropylene,polyvinylidene fluoride, aramide fibers, and perfluoralkoxy fibers. 13.Method according to one of claims 3 through 12, characterized in thatthe material or the synthetic foil, prior to the step of electroless orgalvanic application of a conductive coating, is subjected to etchingand cleaning, followed by activation of the surface.
 14. Methodaccording to claim 13, characterized in that the etching and cleaning isperformed by allowing an atmospheric plasma to react.
 15. Methodaccording to claim 13 or 14, characterized in that the activation takesplace by means of a colloidal palladium compound.
 16. Method accordingto one of claims 2 through 15, characterized in that the substrate isthe material of inherently non-conductive fibers that has been madeconductive.
 17. Method according to claim 16, characterized in that thenon-conductive fibers are glass fibers, mineral fibers, ceramic fibersor synthetic fibers.
 18. Method according to claim 16 or 17,characterized in that the fibers of the material are kept in opposingrelative motion during the electroless or galvanic application of thecoating.
 19. Method according to claim 18, characterized in that thefibers of the material, following electroless or galvanic application ofthe coating, are coated without gaps and are movable relative to oneanother.
 20. Method according to one of claims 1 through 19,characterized in that the dispersion mixture also contains boric acid.21. Method according to one of claims 1 through 20, characterized inthat the dispersion mixture also contains a hypophosphite.
 22. Methodaccording to one of claims 1 through 21, characterized in that thesoluble ionic compound(s) are present in the aqueous dispersion mixturein a total volume of 240 to 380 g/l of dispersion mixture, the lithiumspinel(s) in a volume of 100 to 300 g/l of dispersion mixture, and thetenside in a volume of 1 to 2 ml/l of dispersion mixture.
 23. Methodaccording to one of claims 4 through 22, characterized in that thecarbon is present in the aqueous dispersion mixture in a volume of 1 to5 g/l of solution.
 24. Method according to one of claims 5 through 23,characterized in that the synthetic resin binder is present in theaqueous dispersion mixture in a volume of 5 to 10 g/l of solution. 25.Method according to one of claims 1 through 24, characterized in thatthe electrolessly or galvanically applied coating has a thickness of 0.5μm to 15 μm.
 26. Substrate onto which at least one coating containingone or more lithium-containing spinels and a metal or an alloy isapplied electrolessly or galvanically, obtainable by the methodaccording to one of claims 1 through
 25. 27. Use of the substrateaccording to claim 26 as a cathode in a lithium ion battery.
 28. Methodfor producing an active cathode mass for a lithium ion battery thatcomprises: (a) Production of a mixture of 55 to 75 wt. % of one or morelithium-containing spinels with 25 to 35 wt. % of high conductivity sootand 5 to 10 wt. % of an organic binders, wherein the wt. % relates tothe total weight of the mixture. (b) Addition of a sufficient amount ofhigh-boiling aprotic polar solvent to the mixture from step (a) toproduce a paste with the consistency of a dough; (c) Rolling of thepaste from step (b) into a thin film with a thickness of approximately300 μm to 500 μm; (d) 20- to 24-hour drying of the thin film from step(c) at 50 to 70° C., whereby an active cathode mass is obtained. 29.Method according to claim 26, characterized in that thelithium-containing spinel(s) is(are) selected from the group consistingof LiMn₂O₄, LiCoO₂, LiNiO₂, LiTiS₂ and LiVSe₂, that the binding agent ispolyvinylidene fluoride, and that the high-boiling aprotic polar solventis 1-methyl-2-pyrrolidinone.
 30. Method according to claim 28 or 29,[characterized in that] 30 wt. % of high conductivity soot are used instep (a), that the thin film is rolled to a thickness of 400 μm in step(c), and that the drying in step (d) is performed at 60° C.
 31. Methodfor producing a thin-layer composite cathode for a lithium ion battery,characterized in that the active cathode mass, produced in one of claims28 to 30, is incorporated, by means of calendaring, into a material ofnon-conductive fibers which features a coating of a metal or an alloywhich is suitable for a cathode and is applied electrolessly orgalvanically.
 32. Method according to claim 31, characterized in thatthe metal or the alloy is selected from the group consisting of Ni, Cu,Al, Co, Ag, Au, Pt, Pd, Ru, Rh, NiPCo, NiPMn, NiP, FeNiCr, NiWo, NiPWo,NiSn, CoSn, NiMg, and NiMo.
 33. Method according to claim 32,characterized in that the coating comprises a metal that is selectedfrom the group consisting of Ni, Al, and Ag.
 34. Method according to oneof claims 31 through 33, characterized in that the coating is providedwith an additional coating of aluminum, silver or titanium with athickness of 10 to 100 nm, or carbon.
 35. Method for producing an activeanode mass for a battery that comprises: (a) Production of a mixture of90 to 95 wt. % of graphite with 5 to 10 wt. % of an organic binders,wherein the wt. % relates to the total weight of the mixture. (b)Addition of a sufficient amount of high-boiling aprotic polar solvent tothe mixture from step (a) to produce a paste with the consistency of adough; (c) Rolling of the paste from step (b) into a thin film with athickness of approximately 300 μm to 500 μm; (d) 20- to 24-hour dryingof the thin film from step (c) at 50 to 70° C., whereby an activecathode mass is obtained.
 36. Method according to claim 35,characterized in that the binder in step (a) is polyvinylidene fluoride,that the high-boiling aprotic polar solvent is 1-methyl-2-pyrrolidinone,that the thin film in step (c) is rolled to a thickness of 400 μm, andthat the drying in step (d) takes place at 60° C.
 37. Method forproducing a thin-layer composite cathode for a battery, characterized inthat the active anode mass, produced in claim 35 through 36, isincorporated, by means of calendaring, into a material of non-conductivefibers which features a coating of a metal or an alloy which is suitablefor a anode and is applied electrolessly or galvanically.
 38. Methodaccording to claim 37, characterized in that the electrolessly orgalvanically applied coating comprises copper.
 39. Method according toone of claims 31 through 34, 37 and 38, characterized in that thecalendaring takes place at 130 to 140° C.
 40. Method according to one ofclaims 31 through 34 and 37 to 39, characterized in that the material ofnon-conductive fibers comprises glass fibers, mineral fibers, ceramicfibers, or synthetic fibers.
 41. Method according to claim 40,characterized in that the material of non-conductive fibers comprises amaterial, which is selected from the group consisting of polyester,polytetrafluorethylene, polyamide, polycarbonate, polyethylenimine,polyethylene, polypropylene, polyvinylidene fluoride, aramide fibers,and perfluoralkoxy fibers.
 42. Method according to one of claims 31through 34 and 37 through 41, characterized in that the fibers of thematerial are kept in opposing relative motion during the electroless orgalvanic application of the coating.
 43. Method according to one ofclaims 31 through 34 and 37 through 42, characterized in that the fibersof the material with the galvanically applied coating are coated withoutgaps and are movable relative to one another.
 44. Cathode for a lithiumion battery, obtainable by the method according to one of claims 31through 34 and 39 through
 43. 45. Anode for a battery obtainable by themethod according to one of claims 37 through
 43. 46. Metallized materialof electrically non-conductive fibers, characterized in that the entiresurface of the fibers is coated with a metal or an alloy and that thefibers are movable relative to one another.
 47. Metallized material ofelectrically non-conductive fibers, according to claim 46, characterizedin that the entire surface of the fibers bears an electrolessly orgalvanically applied metal or alloy coating.
 48. Metallized materialaccording to one of claims 46 or 47, characterized in that the thicknessof the metal coating comprises 0.5 μm to 15 μm.
 49. Metallized materialaccording to one of claims 46 through 48, characterized in that thefibers comprise glass fibers, mineral fibers, ceramic fibers, and/orsynthetic fibers.
 50. Metallized material according to claim 49,characterized in that the synthetic fibers comprise fibers of polyester,polytetrafluorethylene, polyamide, polycarbonate, polyethylenimine,polyethylene, polypropylene, polyvinylidene fluoride, aramide fibers,and/or perfluoralkoxy fibers.
 51. Metallized material according to oneof claims 46 through 50, characterized in that the metal or the alloy isselected from the group consisting of Ni, Cu, Al, Co, NiPCo, NiPMn, NiP,FeNiCr, NiWo, NiPWo, NiSn, CoSn, NiMg, NiMo, Ag, Au, Pt, Pd, Ru, and Rh.52. Use of a metallized material according to one of claims 46 through51 for microporous electrodes in electrochemical systems, especially forcurrent deflectors and/or electrodes in electric batteries and fuelcells, for filters, especially for dusts and to clean gas, for catalyticconverters, for alkalic water electrolysis, and for ionizing aircleaning.
 53. Method for producing a metallized material according toone of claims 46 through 51, characterized in that a material ofnon-conductive fibers is subjected to the following steps:
 1. etchingand cleaning of the surface
 2. electroless, galvanic or non-wet-chemicalapplication of an electrically conductive coating, and
 3. electroless orgalvanic metal application during simultaneous, opposing relative motionof the fibers.
 54. Method according to claim 53, characterized in thatstep 2) consists of the application of sulfides and polysulfides,preferably cobalt, manganese, or tin, and an intermediate rinsingprocess and subsequent immersion into a sulfide-containing cross-linkingsolution, and a thereby generated firmly adhering metalsulfide/polysulfide coating.
 55. Method according to claim 53,characterized in that step 2) consists of the following three sub-steps:a) conditioning of the surface, b) activation of the surface, and c)electroless or galvanic metallization.
 56. Method according to one ofclaims 53 through 55, characterized in that step 1) occurs throughatmospheric plasma.
 57. Method according to claim 56, characterized inthat the material is conveyed through a zone of atmospheric plasma in acontinuous operation.
 58. Method according to claims 55 through 57,characterized in that the activation (step b) takes place by means of acolloidal palladium compound.
 59. Method according to claims 53 through58, characterized in that step 3), namely electroless or galvanic metalapplication during simultaneous relative motion of the fibers, takesplace in a continuous operation.
 60. Device for completion of the methodaccording to one of claims 53 through 59, characterized in that at leasttwo rollers (13) for conveying the material (10), at least one of whichhas an elliptical profile, are provided in a galvanizing station or astation for electroless coating (7) to subject the material (10) torhythmic expansion in the direction of conveyance.
 61. Device accordingto claim 60, characterized in that at least one additional roller (14)is provided in the galvanizing station or the station for electrolesscoating (7) to convey the material (10) by means of profiling (15)progressing at a diagonal to the circumferential direction, so that thefibers of the material (10) passing over it are moved back and forth bysaid profiling.
 62. Device according to claim 61, characterized in thatthe galvanizing station or the station for electroless coating featuresa number of consecutive conveying rollers (13) for rhythmic expansion inthe direction of conveyance, which are arranged above the fluid level ofa galvanizing bath or bath for electroless coating (7), wherein anadditional roller (14) is arranged between two such rollers (13) and ispositioned below the fluid level, so that a track of material (10)passes through the galvanizing bath (7) while being rhythmicallyexpanded longitudinally and moved latitudinally.
 63. Substrate of amaterial of non-conductive fibers which has been made conductive, asynthetic foil which has been made conductive, a metal foil or anexpanded metal, which features a coating which comprises a metal or analloy or one or more lithium-containing spinels embedded into the metalor the alloy.
 64. Substrate according to claim 63, characterized in thatthe metal or the alloy is selected from the group consisting of Ni, Cu,Al Co, Ag, Au, Pt, Pd, Ru, Rh, NiPCo, NiPMn, NiP, FeNiCr, NiWo, NiPWo,NiSn, CoSn, NiMg, and NiMo.
 65. Substrate according to claim 63 or 64,characterized in that the spinel(s) are selected from the groupconsisting of LiMn₂O₄, LiCoO₂, LiNiO₂, LiTiS₂ and LiVSe₂.
 66. Substrateaccording to one of claims 63 through 65, characterized in that thenon-conductive fibers of the material comprise glass fibers, mineralfibers, ceramic fibers, or synthetic fibers.